Magnesium-based solid and catalyst component having multimodal pore distribution, and preparation methods therefor

ABSTRACT

A magnesium-based solid, by means of determination based on a nitrogen adsorption method, has a multimodal pore distribution and a specific surface area of not less than 50 m 2 /g, and the pore size distribution of the solid is in a range of 1 nm to 300 nm. There is at least one peak within a pore size range of less than 10 nm, and there is at least another peak within a pore size range of not less than 10 nm. A catalyst is formed using the solid catalyst component is used for propylene polymerization.

CROSS REFERENCE OF RELATED APPLICATIONS

This application claims priority and benefit of CN202011104541.0,CN202011105894.2 and CN202011105648.7, filed on Oct. 15, 2020, which areincorporated herein by reference in their entirety for all purposes.

TECHNICAL FIELD

The present invention relates to the technical field of olefinpolymerization, in particular to a magnesium-based solid substance and acatalyst component for olefin polymerization, and a preparation methodand application thereof.

BACKGROUND ART

Magnesium chloride-supported Ziegler-Natta catalysts are the main olefinpolymerization catalysts currently on the market. In the production ofsuch catalysts, magnesium compound- or magnesium complex-containingsolids can be prepared first as a carrier. For example, the well-knownhigh-speed stirring technology, high-pressure extrusion technology,spray technology, supergravity technology, etc., are all used to preparesuch a carrier, such as a magnesium chloride-alcohol adduct carrier.They are then brought into contact with a titanium-containing compoundto form magnesium chloride-supported, titanium-based catalyst solids, onwhich an internal electron donor compound is then supported to form acatalyst component. Testing of such catalyst components by nitrogenadsorption generally shows a unimodal pore distribution with a mostprobable pore size no more than 10 nm.

In addition, it is also possible to obtain a solution of a magnesiumcompound or complex first, and then bring the solution into contact witha titanium-containing compound to precipitate magnesiumchloride-supported, titanium-based catalyst solids, which are furthercontacted with an internal electron donor compound to form a catalystcomponent. No matter the catalyst components are prepared by the earlypublished patents such as CN85100997A and CN1097597C, or the catalystcomponents are prepared by recently published patents such asCN103619475B and CN107207657A which have adopted emulsion technology tocontrol the crystallization process, there is not a report on amagnesium chloride-supported catalyst component having a multimodal poredistribution.

At present, polyolefin catalysts with a multimodal pore distribution aregenerally prepared by using a molecular sieve or silica gel withmultimodal pore distribution as a carrier. For example, patentsCN104650267A, CN105175586A, CN105330769A and U.S. Pat. No. 5,231,066report that by supporting titanium or a single active site metal on sucha carrier to prepare polyethylene catalyst, polyethylene with bimodal orbroad molecular weight distribution can be obtained. However, it is wellknown that, compared with magnesium chloride-supported catalysts, olefinpolymerization catalysts prepared with molecular sieve- or silicagel-type supports have a relatively low activity.

In addition, in the case where the catalyst component is in anexposed-to-air state, when the structure of the catalyst will be crackedand the internal microporous structure will be destroyed so as totransform into mesopores and macropores, the magnesiumchloride-supported catalyst component may also have a multimodal poredistribution. However, in such a case, the specific surface area of thecatalyst component will decrease sharply or even disappear so that suchcatalyst components with multimodal pore distribution has a very smallspecific surface area and the catalysts can basically not work.

There remains a need for magnesium-based catalyst supports that exhibitdesired properties, polyolefin catalyst components prepared therefrom,and corresponding catalyst systems.

SUMMARY OF THE INVENTION

A first object of the present invention is to provide a magnesium-basedsolid with multimodal pore distribution, which comprises a magnesiumhalide as a carrier, contains titanium element, and is featured by amultimodal pore size distribution in combination with a high specificsurface area.

A second object of the present invention is to provide a method forpreparing the magnesium-based solid associated with the first object.

A third object of the present invention is to provide a solid catalystcomponent for olefin polymerization prepared from the magnesium-basedsolid.

A fourth object of the present invention is to provide a method forpreparing the solid catalyst component for olefin polymerizationassociated with the third object.

A fifth object of the present invention is to provide an olefinpolymerization catalyst comprising the catalyst component.

A sixth object of the present invention is to provide the use of thecatalyst in olefin polymerization.

A seventh object of the present invention is to provide an olefinpolymerization method associated with the above object.

The inventors have found that when the olefin polymerization catalystprepared by using the magnesium-based solid with multimodal poredistribution is used for propylene polymerization, it has higherpolymerization activity and higher stereo-orientation ability, and thepolymer prepared by using the catalyst of the present invention inpropylene polymerization has a broader molecular weight distributionthan those achieved by the known techniques using the same internalelectron donor.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In a first aspect, the present invention provides a magnesium-basedsolid with a multimodal pore distribution, which comprises a magnesiumhalide as a carrier and titanium element, wherein, as determined by anitrogen adsorption method, the magnesium-based solid has a specificsurface area of no less than 50 m²/g and a pore size distribution in arange of from 1 nm to 300 nm, wherein there are at least one peak withinthe pore size range of less than 10 nm and at least one peak within thepore size range of not less than 10 nm.

According to the present invention, the pore size distribution of themagnesium-based solid is obtained by measuring with nitrogen adsorptionmethod and calculating with NLDFT algorithm.

According to the present invention, the specific surface area of themagnesium-based solid is obtained by measuring with nitrogen adsorptionmethod.

According to some embodiments of the present invention, themagnesium-based solids have a spherical or spherical-like structure.

In some preferred embodiments of the present invention, the mostprobable pore size corresponding to the peak within the pore size rangeof less than 10 nm is in a range of from 2 nm to 8 nm, preferably from 2nm to 6 nm; and at the same time, the most probable pore sizecorresponding to the peak within the pore size range of not less than 10nm is in a range of from 15 nm to 200 nm, preferably from 20 nm to 100nm, and more preferably from 30 nm to 90 nm.

In some preferred embodiments of the present invention, in themagnesium-based solids, the ratio of the pore volume of pores with apore size of less than 10 nm to the pore volume of pores with a poresize of not less than 10 nm is (0.1-20):1, and preferably (0.25-15): 1.

In some preferred embodiments of the present invention, the pore volumeof pores with a pore size of less than 5 nm accounts for 10% to 90% ofthe total pore volume, and preferably 15% to 70%; and the pore volume ofpores with a pore size of not less than 30 nm accounts for 5% to 70% ofthe total pore volume, and preferably 10% to 60%.

In some preferred embodiments of the present invention, themagnesium-based solids have a specific surface area of from 100 m²/g to500 m²/g.

In a second aspect, the present invention provides a method forpreparing the above-described magnesium-based solid, comprising:

-   -   S1. contacting a magnesium halide with a Lewis base in an        organic solvent to form a magnesium-containing solution;    -   S2. contacting the magnesium-containing solution with an inert        dispersion medium and a Lewis acid to form a mixture;    -   S3. in the presence of an auxiliary precipitant and a        surfactant, precipitating the magnesium-based solid from the        mixture,    -   wherein, in step S1, the Lewis base includes an organic        phosphorus compound, which is used in an amount of from 1.5 to        10 moles per mole of the magnesium halide; and in step S2, the        Lewis acid includes a titanium compound.

In some preferred embodiments of the present invention, in step S1, theLewis base includes an organic phosphorus compound, which is used in anamount of from 2 to 5 moles per mole of the magnesium halide.

According to the present invention, in step S2, the mixture is in theform of colloids, two-phase solutions, emulsions and others. Preferably,the mixture is formed into a mixture comprising at least two liquidphases. Thus, one or more processes such as vibration, stirring,atomization, shearing, etc., can be used to promote the formation of auniform emulsion from the mixture in the presence of the surfactant, sothat spherical solids can be solidified and precipitated.

In some preferred embodiments of the present invention, in step S3, themixture is heated up to a target temperature to cause the precipitationof the magnesium-based solids from the mixture, wherein the targettemperature ranges from 50 to 110° C.

In some preferred embodiments of the present invention, in step S3,after the heating-up process is completed, the target temperature ismaintained for 0.1 to 24 h with stirring.

According to the present invention, after the precipitation of thesolids from the mixture, the suspension can be stirred at a certaintemperature for a certain period of time, such as 10 minutes to 24hours, in order to make the precipitates more stable in morphology andimprove the particle strength.

In some preferred embodiments of the present invention, in step S3, theheating-up process takes from 0.01 h to 36 h, and preferably from 0.1 hto 24 h.

According to the present invention, the process of heating-up themixture is not particularly limited, and any known process forheating-up can be used, such as slowly, stepwise, rapidly or programmedheating-up. The specific heating-up manner can be adjusted according tothe specific formulation, contact temperature, etc. The inventors havefound through investigation that, in the preparation method describedherein, when other conditions are the same, different heating-upprocesses will affect the particle morphology and particle sizedistribution of the final catalyst. Specifically, a better particlemorphology can be obtained if a slow heating-up process is used, whereasa too fast heating rate will lead to a poor particle morphology.Therefore, the process of heating-up the mixture can last for 1 minuteto 36 hours, and preferably 3 minutes to 24 hours.

In some preferred embodiments of the present invention, the magnesiumhalide used in step 51 is represented by the general formula (1):

MgX¹ ₂  (1),

wherein X¹ is a halogen, preferably chlorine, bromine or iodine.

In some preferred embodiments of the present invention, the magnesiumhalide is one or more of magnesium dichloride, magnesium dibromide andmagnesium diiodide.

In some preferred embodiments of the present invention, the magnesiumhalide is magnesium dichloride.

In some preferred embodiments of the present invention, the organicphosphorus compound is one or more selected from the compoundsrepresented by formula (2) or formula (3):

wherein R¹, R², R³, R⁴, R⁵, R⁶ each independently have 1-20 carbon atomsand are selected from linear or branched alkyl groups, cycloalkylgroups, aromatic hydrocarbon groups, and aromatic hydrocarbon groupshaving a substituent such as an alkyl group.

In some preferred embodiments of the present invention, the organicphosphorus compound is one or more of trimethyl phosphate, triethylphosphate, tributyl phosphate, tripentyl phosphate, triphenyl phosphate,tris(o-, m- or p-tolyl) phosphate, trimethyl phosphite, triethylphosphite, tributyl phosphite and tribenzyl phosphite.

According to the present invention, the organic phosphorus compound istributyl phosphate.

In some preferred embodiments of the present invention, the organicsolvent is one or more selected from aromatic hydrocarbon compounds andhalogenated hydrocarbon compounds.

In some preferred embodiments of the present invention, the organicsolvent is one or more of toluene, ethylbenzene, benzene, xylenes andchlorobenzene.

According to some preferred embodiments of the present invention, theorganic solvent is toluene.

In some preferred embodiments of the present invention, the organicsolvent is used in an amount of from 1 to 40 moles, and preferably from2 to 30 moles, relative to one mole of the magnesium halide.

According to some embodiments of the present invention, the Lewis basefurther includes an organic epoxy compound and/or a hydroxyl-containingcompound.

According to the present invention, the organic epoxy compound is one ormore of the oxidation products of aliphatic olefins and halogenatedaliphatic olefins with 2-8 carbon atoms, and specifically can be one ormore of ethylene oxide, propylene oxide, epoxychloroethane,epichlorohydrin, butylene oxide, butadiene oxide, butadiene dioxide,methyl glycidyl ether and diglycidyl ether, preferably epichlorohydrin.

According to the present invention, the hydroxyl-containing compound hasa general formula of HOR, wherein R is a hydrocarbon group having 2-20carbon atoms, which can be a saturated or unsaturated, linear orbranched alkyl group, a cycloalkyl group or an aromatic hydrocarbongroup. The hydroxyl-containing compound is preferably an alcoholcompound, and more preferably one or more of ethanol, propanol, butanol,2-ethylhexanol, benzyl alcohol and phenethyl alcohol.

According to the present invention, the organic epoxy compound is usedin an amount of from 0.1 to 10 moles, and preferably from 0.4 to 4moles, relative to one mole of the magnesium halide.

According to the present invention, the hydroxyl-containing compound isused in an amount of from 0.1 to 10 moles, and preferably from 0.1 to 5moles, relative to one mole of the magnesium halide.

According to the present invention, the magnesium-containing solutioncan be formed by contacting the magnesium halide and the organicphosphorus compound in the organic solvent; it can also be formed bycontacting the magnesium halide, the organic epoxy compound and theorganic phosphorus compound in the organic solvent; or it can also beformed by contacting the magnesium halide, the organic epoxy compound,the organic phosphorus compound, and the hydroxyl-containing compound inthe organic solvent.

The contact process for forming the magnesium-containing solutiondescribed in the present invention is not particularly limited. Thepurpose of the contact is to form a magnesium-containing uniformsolution. The conditions for the contact include: a contact temperatureof from 10 to 150° C., preferably from 30 to 130° C., and a contact timeof from 0.05 to 10 hours, preferably from 0.1 to 6 hours.

In some preferred embodiments of the present invention, in step S2, theinert dispersion medium is one or more selected from kerosenes, paraffinoils, white oils, vaseline oils, methyl silicone oils, aliphatic andcycloaliphatic hydrocarbons.

In some preferred embodiments of the present invention, in step S2, theinert dispersion medium is one or more selected from white oils, hexanesand decanes.

In some preferred embodiments of the present invention, in step S2, theamount of the inert dispersion medium used is from 0.1 g to 300 g,preferably from 1 g to 150 g, relative to one gram of the magnesiumhalide.

In some preferred embodiments of the present invention, the Lewis acidcomprises a titanium-containing compound and optionally asilicon-containing compound, the titanium-containing compound beingrepresented by the general formula (4):

TiX² _(m)(OR¹)_(4-m)  (4)

wherein X² is a halogen, preferably chlorine, bromine or iodine, le is ahydrocarbon group having 1-carbon atoms, and m is an integer of 1 to 4.

In some preferred embodiments of the present invention, thetitanium-containing compound is one or more selected from titaniumtetrachloride, titanium tetrabromide, titanium tetraiodide, titaniumtetrabutoxide, titanium tetraethoxide, triethoxy titanium chloride,diethoxy titanium dichloride and ethoxy titanium trichloride.

In some preferred embodiments of the present invention, thetitanium-containing compound is used in an amount of from 0.5 to 25moles, preferably from 1 to 20 moles, relative to one mole of themagnesium halide.

In some preferred embodiments of the present invention, thesilicon-containing compound is represented by the general formula (5):

SiX³ _(n)R² _(4-n)  (5)

wherein X³ is a halogen, preferably chlorine, bromine or iodine, R² is ahydrocarbon group having 1-carbon atoms, and n is an integer of from 1to 4.

In some preferred embodiments of the present invention, thesilicon-containing compound is silicon tetrachloride.

In some preferred embodiments of the present invention, thesilicon-containing compound is used in an amount of from 0.1 to 40moles, preferably from 0.1 to 20 moles, relative to one mole of themagnesium halide.

According to the present invention, in step S2, the contacting of themagnesium-containing solution, the inert dispersion medium and the Lewisacid to form a mixture can be carried out by any manner. For example, itis possible to contact the magnesium-containing solution with the inertdispersion medium first, and then add dropwise the Lewis acid thereto;it is also possible to contact the magnesium-containing solution withthe Lewis acid first, and then add the inert dispersion medium thereto;alternatively, it is also possible to contact the inert dispersionmedium with the Lewis acid, and then with the magnesium-containingsolution.

In some preferred embodiments of the present invention, in step S3, theauxiliary precipitant is one or more selected from organic acids,organic acid anhydrides, organic ethers and organic ketones.

In some preferred embodiments of the present invention, in step S3, theauxiliary precipitant is one or more selected from acetic anhydride,phthalic anhydride, succinic anhydride, maleic anhydride, pyromelliticdianhydride, acetic acid, propionic acid, butyric acid, acrylic acid,methacrylic acid, acetone, methyl ethyl ketone, benzophenone, dimethylether, diethyl ether, dipropyl ether, dibutyl ether and dipentyl ether.

In some preferred embodiments of the present invention, in step S3, theamount of the auxiliary precipitant used is from 0.01 to 1 mole,preferably from 0.04 to 0.4 moles, relative to one mole of the magnesiumhalide.

In some preferred embodiments of the present invention, in step S3, thesurfactant is a polymeric surfactant.

In some preferred embodiments of the present invention, in step S3, thesurfactant is one or more selected from the group consisting of alkyl(meth)acrylate polymers, alkyl (meth)acrylate copolymers, alcoholysatesof maleic anhydride polymers, and the alcoholysates of maleic anhydridecopolymers.

In some preferred embodiments of the present invention, in step S3, thesurfactant includes specifically at least one of alcoholysates of maleicanhydride polymers, alcoholysates of maleic anhydride-styrenecopolymers, alcoholysates of maleic anhydride-styrene-alkyl(meth)acrylate terpolymers, alcoholysates of maleic anhydride-alkyl(meth)acrylate copolymers, wherein the alkyl chain in the alkyl(meth)acrylate is a chain of linear or branched alkanes, cycloalkanes oraromatic hydrocarbons with 1-30 carbon atoms, preferably 1-20 carbonatoms; the maleic anhydride copolymer refers to a copolymer comprisingat least one maleic anhydride monomer; the alcoholysate refers to apolymeric product obtained by reacting the polymer in question with analcohol compound having a structure formula of, for example, ROH,wherein R is a linear or branched alkyl, a cycloalkyl, or an aromatichydrocarbyl, having 2 to 20 carbon atoms.

In some preferred embodiments of the present invention, the surfactantused in the present invention comprises at least one of alkyl(meth)acrylate polymers and alkyl (meth)acrylate copolymers, such as atleast one of poly(alkyl (meth)acrylate)s, alkyl (meth)acrylate-maleicanhydride copolymers, and alkyl (meth)acrylate-maleic anhydride-styrenecopolymers; wherein the ester side chains are chains of linear orbranched alkanes, cycloalkanes or aromatic hydrocarbons with 1-30 carbonatoms, preferably 1-20 carbon atoms.

Various surfactants useful in the present invention are commerciallyavailable. For example, the poly(meth)acrylate polymer surfactants canbe purchased from Guangzhou Ruishengyan Chemical Technology Co., Ltd. aspour point depressant products under the tradenames of T602, T632 andthe like.

In the preparation method according to the present invention, theaddition position of the surfactant may be any position in thepreparation method, and the surfactant may be added in one or moreparts. According to the present invention, the surfactant may be addedin one or more parts during or after the formation of themagnesium-containing solution; in one part to the inert dispersionmedium; in a part to the inert dispersion medium and in another part tothe magnesium-containing solution; or after the magnesium-containingsolution, the inert dispersion medium and the Lewis acid are contacted.

In step S3, if the surfactant, especially the above-mentionedsurfactant, is not used, the resultant magnesium-based solid will bepowdery, and no magnesium-based solid with spherical or spherical-likestructure can be obtained.

In some preferred embodiments of the present invention, in step S3, theamount of the surfactant used is from 0.01 g to 5 g, preferably from0.05 g to 1 g, relative to one gram of the magnesium halide.

In a third aspect, the present invention provides a solid catalystcomponent for olefin polymerization with a multimodal pore distribution,which comprises the above-described magnesium-based solid and at leastone internal electron donor.

According to the present invention, as measured by the nitrogenadsorption method, the solid catalyst component has a pore sizedistribution exhibiting multiple peaks and a specific surface area ofnot less than 50 m²/g; wherein the pore size distribution exhibitingmultiple peaks of the solid is such that there are at least one peak inthe pore size range of 1 nm to 100 nm and at least another peak in thepore size range of 5 nm to 200 nm.

Preferably, as measured by the nitrogen adsorption method, the solidcatalyst component has a pore size distribution exhibiting multiplepeaks and a specific surface area of not less than 50 m²/g; wherein thepore size distribution exhibiting multiple peaks of the solid catalystcomponent is such that there are at least a first peak in the pore sizerange of 1 nm to 10 nm and at least a second peak in the pore size rangeof 10 nm to 200 nm.

According to the present invention, the pore size distribution iscalculated by using the NLDFT algorithm on the data measured by thenitrogen adsorption method.

In some preferred embodiments of the present invention, the pore sizedistribution exhibiting multiple peaks of the solid catalyst componentis such that the at least one peak in the pore size range of 1 nm-100 nmhas a most probable pore size of from 1 nm to 50 nm, preferably from 1nm to 10 nm, more preferably from 2 nm to 8 nm, and further preferablyfrom 3 nm to 6 nm; and the at least another peak in the pore size rangeof 5 nm-200 nm has a most probable pore size of from 10 nm to 200 nm,preferably from 20 nm to 100 nm, and more preferably from 30 nm to 90nm.

Preferably, the pore size distribution exhibiting multiple peaks of thesolid catalyst component is such that the peak in the pore size range of1 nm-10 nm has a most probable pore size of from 2 nm to 8 nm, andfurther preferably from 2 nm to 6 nm; and the peak in the pore sizerange of 10 nm-200 nm has a most probable pore size of from 15 nm to 200nm, preferably from 20 nm to 100 nm, and more preferably from 30 nm to90 nm.

In some preferred embodiments of the present invention, the pore volumeof pores with a pore size of less than 5 nm accounts for 10% to 90%,preferably 15% to 70% of the total pore volume; and the pore volume ofpores with a pore size of not less than 30 nm accounts for 5% to 70%,preferably 10% to 60% of the total pore volume.

In some preferred embodiments of the present invention, the solids havea specific surface area of not less than 100 m²/g, and preferably notless than 150 m²/g.

According to the present invention, the internal electron donor can bevarious internal electron donors commonly used in the art, preferablyone or more selected from esters, ethers, ketones, amines, and silanes,preferably at least one of aliphatic mono- or poly-carboxylic acidesters, aromatic carboxylic acid esters, diol ester compounds anddiether compounds, and preferably includes at least one of dibasicaliphatic carboxylic acid esters, aromatic carboxylic acid esters, diolesters and diether compounds.

Specific examples of internal electron donor compounds suitable for usein the present invention include, but are not limited to, diethylphthalate, diisobutyl phthalate, di-n-butyl phthalate, diisooctylphthalate, di-n-octyl phthalate, diethyl malonate, dibutyl malonate,diethyl adipate, dibutyl adipate, diethyl sebacate, dibutyl sebacate,diethyl maleate, di-n-butyl maleate, diethyl naphthalene dicarboxylate,dibutyl naphthalene dicarboxylate, triethyl trimellitate, tributyltrimellitate, triethyl 1,2,3-benzenetricarboxylate, tributyl1,2,3-benzenetricarboxylate, tetraethyl pyromellitate, tetrabutylpyromellitate, 1,3-propanediol dibenzoate, 2-methyl-1,3-propanedioldibenzoate, 2-ethyl-1,3-propanediol dibenzoate, 2-propyl-1,3-propanedioldibenzoate, 2-butyl-1,3-propanediol dibenzoate,2,2-dimethyl-1,3-propanediol dibenzoate, 2-ethyl-2-butyl-1,3-propanedioldibenzoate, 2,2-diethyl-1,3-propanediol dibenzoate,2-methyl-2-propyl-1,3-propanediol dibenzoate,2-isopropyl-2-isopentyl-1,3-propanediol dibenzoate, 2,4-pentanedioldibenzoate, 3-methyl-2,4-pentanediol dibenzoate, 3-ethyl-2,4-pentanedioldibenzoate, 3-propyl-2,4-pentanediol dibenzoate, 3-butyl-2,4-pentanedioldibenzoate, 3,3-dimethyl-2,4-pentanediol dibenzoate,2-methyl-1,3-pentanediol dibenzoate, 2,2-dimethyl-1,3-pentanedioldibenzoate, 2-ethyl-1,3-pentanediol dibenzoate, 2-butyl-1,3-pentanedioldibenzoate, 2-methyl-1,3-pentanediol dibenzoate, 2-ethyl-1,3-pentanedioldibenzoate, 2-propyl-1,3-pentanediol dibenzoate, 2-butyl-1,3-pentanedioldibenzoate, 2,2-dimethyl-1,3-pentanediol dibenzoate,2-methyl-1,3-pentanediol dibenzoate, 2,2-dimethyl-1,3-pentanedioldibenzoate, 2-ethyl-1,3-pentanediol dibenzoate, 2-butyl-1,3-pentanedioldibenzoate, 2,2,4-trimethyl-1,3-pentanediol dibenzoate,3-methyl-3-butyl-2,4-pentanediol dibenzoate,2,2-dimethyl-1,5-pentanediol dibenzoate, 1,6-hexanediol dibenzoate,6-heptene-2,4-diol dibenzoate, 2-methyl-6-heptene-2,4-diol dibenzoate,3-methyl-6-heptene-2,4-diol dibenzoate, 4-methyl-6-heptene-2,4-dioldibenzoate, 5-methyl-6-heptene-2,4-diol dibenzoate,6-methyl-6-heptene-2,4-diol dibenzoate, 3-ethyl-6-heptene-2,4-dioldibenzoate, 4-ethyl-6-heptene-2,4-diol dibenzoate,5-ethyl-6-heptene-2,4-diol dibenzoate, 6-ethyl-6-heptene-2,4-dioldibenzoate, 3-propyl-6-heptene-2,4-diol dibenzoate,4-propyl-6-heptene-2,4-diol dibenzoate, 5-propyl-6-heptene-2,4-dioldibenzoate, 6-propyl-6-heptene-2,4-diol dibenzoate,3-butyl-6-heptene-2,4-diol dibenzoate, 4-butyl-6-heptene-2,4-dioldibenzoate, 5-butyl-6-heptene-2,4-diol dibenzoate,6-butyl-6-heptene-2,4-diol dibenzoate, 3,5-dimethyl-6-heptene-2,4-dioldibenzoate, 3,5-diethyl-6-heptene-2,4-diol dibenzoate,3,5-dipropyl-6-heptene-2,4-diol dibenzoate,3,5-dibutyl-6-heptene-2,4-diol dibenzoate,3,3-dimethyl-6-heptene-2,4-diol dibenzoate,3,3-diethyl-6-heptene-2,4-diol dibenzoate,3,3-dipropyl-6-heptene-2,4-diol dibenzoate,3,3-dibutyl-6-heptene-2,4-diol dibenzoate, 3,5-heptanediol dibenzoate,2-methyl-3,5-heptanediol dibenzoate, 3-methyl-3,5-heptanedioldibenzoate, 4-methyl-3,5-heptanediol dibenzoate,5-methyl-3,5-heptanediol dibenzoate, 6-methyl-3,5-heptanedioldibenzoate, 3-ethyl-3,5-heptanediol dibenzoate, 4-ethyl-3,5-heptanedioldibenzoate, 5-ethyl-3,5-heptanediol dibenzoate, 3-propyl-3,5-heptanedioldibenzoate, 4-propyl-3,5-heptanediol dibenzoate, 3-butyl-3,5-heptanedioldibenzoate, 2,3-dimethyl-3,5-heptanediol dibenzoate,2,4-dimethyl-3,5-heptanediol dibenzoate, 2,5-dimethyl-3,5-heptanedioldibenzoate, 2,6-dimethyl-3,5-heptanediol dibenzoate,3,3-dimethyl-3,5-heptanediol dibenzoate, 4,4-dimethyl-3,5-heptanedioldibenzoate, 6,6-dimethyl-3,5-heptanediol dibenzoate,2,6-dimethyl-3,5-heptanediol dibenzoate, 3,4-dimethyl-3,5-heptanedioldibenzoate, 3,5-dimethyl-3,5-heptanediol dibenzoate,3,6-dimethyl-3,5-heptanediol dibenzoate, 4,5-dimethyl-3,5-heptanedioldibenzoate, 4,6-dimethyl-3,5-heptanediol dibenzoate,4,4-dimethyl-3,5-heptanediol dibenzoate, 6,6-dimethyl-3,5-heptanedioldibenzoate, 2-methyl-3-ethyl-3,5-heptanediol dibenzoate,2-methyl-4-ethyl-3,5-heptanediol dibenzoate, 2-methyl-dibenzoate,3-methyl-3-ethyl-3,5-heptanediol dibenzoate,3-methyl-4-ethyl-3,5-heptanediol dibenzoate,3-methyl-5-ethyl-3,5-heptanediol dibenzoate,4-methyl-3-ethyl-3,5-heptanediol dibenzoate,4-methyl-4-ethyl-3,5-heptanediol dibenzoate,4-methyl-5-ethyl-3,5-heptanediol dibenzoate,2-methyl-3-propyl-3,5-heptanediol dibenzoate,2-methyl-4-propyl-3,5-heptanediol dibenzoate,2-methyl-5-propyl-3,5-heptanediol dibenzoate,3-methyl-3-propyl-3,5-heptanediol dibenzoate,3-methyl-4-propyl-3,5-heptanediol dibenzoate,3-methyl-5-propyl-3,5-heptanediol dibenzoate,4-methyl-3-propyl-3,5-heptanediol dibenzoate,4-methyl-4-propyl-3,5-heptanediol dibenzoate,4-methyl-5-propyl-3,5-heptanediol dibenzoate,2-(2-ethylhexyl)-1,3-dimethoxypropane, 2-isopropyl-1,3-dimethoxypropane,2-butyl-1,3-dimethoxypropane, 2-secbutyl-1,3-dimethoxypropane,2-cyclohexyl-1,3-dimethoxypropane, 2-phenyl-1,3-dimethoxypropane,2-(2-phenyl ethyl)-1,3-dimethoxypropane,2-(2-cyclohexylethyl)-1,3-dimethoxypropane,2-(p-chlorophenyl)-1,3-dimethoxypropane,2-diphenylmethyl-1,3-dimethoxypropane,2,2-dicyclohexyl-1,3-dimethoxypropane,2,2-dicyclopentyl-1,3-dimethoxypropane,2,2-diethyl-1,3-dimethoxypropane, 2,2-dipropyl-1,3-dimethoxypropane,2,2-diisopropyl-1,3-dimethoxypropane, 2,2-dibutyl-1,3-dimethoxypropane,2-methyl-2-propyl-1,3-dimethoxypropane,2-methyl-2-benzyl-1,3-dimethoxypropane,2-methyl-2-ethyl-1,3-dimethoxypropane,2-methyl-2-isopropyl-1,3-dimethoxypropane,2-methyl-2-phenyl-1,3-dimethoxypropane,2-methyl-2-cyclohexyl-1,3-dimethoxypropane, 2,2-bis(2-cyclohexylethyl)-1,3-dimethoxypropane, 2-methyl-2-isobutyl-1,3-dimethoxypropane,2-methyl-2-(2-ethylhexyl)-1,3-dimethoxypropane,2,2-diisobutyl-1,3-dimethoxypropane, 2,2-diphenyl-1,3-dimethoxypropane,2,2-dibenzyl-1,3-dimethoxypropane,2,2-bis(cyclohexylmethyl)-1,3-dimethoxypropane,2-isobutyl-2-isopropyl-1,3-dimethoxypropane,2-(1-methylbutyl)-2-isopropyl-1,3-dimethoxypropane,2-isopropyl-2-isopentyl-1,3-dimethoxypropane,2-phenyl-2-isopropyl-1,3-dimethoxypropane,2-phenyl-2-sec-butyl-1,3-dimethoxypropane,2-benzyl-2-isopropyl-1,3-dimethoxypropane,2-cyclopentyl-2-isopropyl-1,3-dimethoxypropane,2-cyclopentyl-2-sec-butyl-1,3-dimethoxypropane,2-cyclohexyl-2-isopropyl-1,3-dimethoxypropane,2-cyclohexyl-2-sec-butyl-1,3-dimethoxypropane,2-isopropyl-2-sec-butyl-1,3-dimethoxypropane,2-cyclohexyl-2-cyclohexylmethyl-1,3-dimethoxypropane,9,9-dimethoxymethylfluorene, ethylene glycol dimethyl ether, ethyleneglycol diethyl ether, ethylene glycol dibutyl ether, butylene glycoldimethyl ether, butylene glycol diethyl ether, butylene glycol dibutylether, hexanediol dimethyl ether, hexanediol diethyl ether, hexanedioldibutyl ether, diethyl 2,2-dimethylsuccinate, diethyl2-ethyl-2-methylsuccinate, diethyl 2-benzyl-2-isopropylsuccinate,diethyl 2-cyclohexylmethyl-2-isobutylsuccinate, diethyl2-cyclopentyl-2-n-butylsuccinate, diethyl 2,2-diisobutylsuccinate,diethyl 2-cyclohexyl-2-ethyl succinate, diethyl2-isopropyl-2-methylsuccinate, diethyl 2-tetradecyl-2-ethyl succinate,diethyl 2-isobutyl-2-ethyl succinate, diethyl2-(1-trifluoromethyl-ethyl)-2-methylsuccinate, diethyl2-isopentyl-2-isobutylsuccinate, diethyl 2-phenyl-2-n-butylsuccinate,diisobutyl 2,2-dimethylsuccinate, diisobutyl 2-ethyl-2-methylsuccinate,diisobutyl 2-benzyl-2-isopropylsuccinate, diisobutyl2-cyclohexylmethyl-2-isobutylsuccinate, diisobutyl2-cyclopentyl-2-n-butylsuccinate, diisobutyl 2,2-diisobutylsuccinate,diisobutyl 2-cyclohexyl-2-ethyl succinate, diisobutyl2-isopropyl-2-methylsuccinate, diisobutyl 2-tetradecyl-2-ethylsuccinate, diisobutyl 2-isobutyl-2-ethyl succinate, diisobutyl2-(1-trifluoromethyl-ethyl)-2-methylsuccinate, diisobutyl2-isopentyl-2-isobutylsuccinate, diisobutyl 2-phenyl-2-n-butylsuccinate,dineopentyl 2,2-dimethylsuccinate, dineopentyl2-ethyl-2-methylsuccinate, dineopentyl 2-benzyl-2-isopropylsuccinate,dineopentyl 2-cyclohexylmethyl-2-isobutylsuccinate, dineopentyl2-cyclopentyl-2-n-butylsuccinate, dineopentyl 2,2-diisobutylsuccinate,dineopentyl 2-cyclohexyl-2-ethylsuccinate, dineopentyl2-isopropyl-2-methylsuccinate, dineopentyl2-tetradecyl-2-ethylsuccinate, dineopentyl 2-isobutyl-2-ethylsuccinate,dineopentyl 2-(1-trifluoromethyl-ethyl)-2-methylsuccinate, dineopentyl2-isopentyl-2-isobutylsuccinate, dineopentyl2-phenyl-2-n-butylsuccinate, diethyl 2,3-bis(trimethylsilyl)succinate,diethyl 2,2-sec-butyl-3-methylsuccinate, diethyl2-(3,3,3-trifluoropropyl)-3-methylsuccinate, diethyl2,3-bis(2-ethyl-butyl)succinate, diethyl2,3-diethyl-2-isopropylsuccinate, diethyl2,3-diisopropyl-2-methylsuccinate, diethyl2,3-dicyclohexyl-2-methylsuccinate, diethyl 2,3-dibenzyl succinate,diethyl 2,3-diisopropylsuccinate, diethyl2,3-bis(cyclohexylmethyl)succinate, diethyl 2,3-di-tert-butylsuccinate,diethyl 2,3-diisobutylsuccinate, diethyl 2,3-dineopentylsuccinate,diethyl 2,3-diisopentylsuccinate, diethyl2,3-(1-trifluoromethyl-ethyl)succinate, diethyl 2,3-tetradecylsuccinate,diethyl 2,3-fluorenylsuccinate, diethyl 2-isopropyl-3-isobutylsuccinate,diethyl 2-tert-butyl-3-isopropylsuccinate, diethyl2-isopropyl-3-cyclohexylsuccinate, diethyl2-isopentyl-3-cyclohexylsuccinate, diethyl2-tetradecyl-3-cyclohexylmethylsuccinate, diethyl2-cyclohexyl-3-cyclopentylsuccinate, diisobutyl2,3-diethyl-2-isopropylsuccinate, diisobutyl2,3-diisopropyl-2-methylsuccinate, diisobutyl 2,3-dicyclohexyl-2-methylsuccinate, diisobutyl 2,3-dibenzyl succinate,diisobutyl 2,3-diisopropylsuccinate, diisobutyl2,3-bis(cyclohexylmethyl)succinate, diisobutyl2,3-di-tert-butylsuccinate, diisobutyl 2,3-diisobutyl succinate,diisobutyl 2,3-dineopentylsuccinate, diisobutyl2,3-diisopentylsuccinate, diisobutyl2,3-(1-trifluoromethyl-ethyl)succinate, diisobutyl2,3-tetradecylsuccinate, diisobutyl 2,3-fluorenylsuccinate, diisobutyl2-isopropyl-3-isobutylsuccinate, diisobutyl2-tert-butyl-3-isopropylsuccinate, diisobutyl2-isopropyl-3-cyclohexylsuccinate, diisobutyl2-isopentyl-3-cyclohexylsuccinate, diisobutyl2-tetradecyl-3-cyclohexylmethylsuccinate, diisobutyl2-cyclohexyl-3-cyclopentylsuccinate, dineopentyl 2,3-bis(trimethylsilyl)succinate, dineopentyl 2,2-sec-butyl-3-methylsuccinate,dineopentyl 2-(3,3,3-trifluoropropyl)-3-methylsuccinate, dineopentyl2,3-bis(2-ethyl-butyl)succinate, dineopentyl2,3-diethyl-2-isopropylsuccinate, dineopentyl2,3-diisopropyl-2-methylsuccinate, dineopentyl2,3-dicyclohexyl-2-methylsuccinate, dineopentyl 2,3-dibenzylsuccinate,dineopentyl 2,3-diisopropylsuccinate, dineopentyl2,3-bis(cyclohexylmethyl)succinate, dineopentyl2,3-di-tert-butylsuccinate, dineopentyl 2,3-diisobutylsuccinate,dineopentyl 2,3-dineopentylsuccinate, dineopentyl2,3-diisopentylsuccinate, dineopentyl2,3-(1-trifluoromethyl-ethyl)succinate, dineopentyl2,3-tetradecylsuccinate, dineopentyl 2,3-fluorenylsuccinate, dineopentyl2-isopropyl-3-isobutylsuccinate, dineopentyl2-tert-butyl-3-isopropylsuccinate, dineopentyl2-isopropyl-3-cyclohexylsuccinate, dineopentyl2-isopentyl-3-cyclohexylsuccinate, dineopentyl2-tetradecyl-3-cyclohexylmethylsuccinate, dineopentyl2-cyclohexyl-3-cyclopentyl succinate.

Further, preferred internal electron donors are at least one ofdi-n-butyl phthalate, diisobutyl phthalate, 2,4-pentanediol dibenzoate,3,5-heptanediol dibenzoate, diethyl 2,3-diisopropylsuccinate, diisobutyl2,3-diisopropylsuccinate, di-n-butyl 2,3-diisopropylsuccinate, dimethyl2,3-diisopropylsuccinate, diisobutyl 2,2-dimethylsuccinate, diisobutyl2-ethyl-2-methylsuccinate, diethyl 2-ethyl-2-methylsuccinate,2-isopropyl-2-isopentyl-1,3-dimethoxypropane,9,9-dimethoxymethylfluorene, ethylene glycol dibutyl ether.

According to the present invention, the addition amount of the internalelectron donor is not particularly limited, and it can be onesconventionally used in the art. Preferably, the molar ratio of theinternal electron donor to the magnesium halide is 0.001-1:1, andpreferably 0.01-1:1.

In a fourth aspect, the present invention provides a method forpreparing a solid catalyst component for olefin polymerization,including:

-   -   method 1, where at least one internal electron donor is added        during the preparation of the above-described magnesium-based        solid to obtain the solid catalyst component for olefin        polymerization; or    -   method 2, where at least one internal electron donor is added        during the preparation of the above-described magnesium-based        solid, and the precipitated solids continue to contact with at        least one internal electron donor to obtain the solid catalyst        component for olefin polymerization; or    -   method 3, where at least one internal electron donor is        contacted with the above-described magnesium-based solid to        obtain the solid catalyst component for olefin polymerization.

According to the present invention, in the method 1 and the method 2,the internal electron donor can be added at any timing in thepreparation process of the magnesium-based solid and in one or moreparts.

According to the present invention, the timing, at which the internalelectron donor is added in the method 1 and the method 2, includes thatthe internal electron donor is added in one or more parts to themagnesium-containing homogeneous solution in step S1, and that theinternal electron donor is added in one or more parts after the mixturein step S2 is formed and in the process of precipitation by heating-upin step S3.

In a fifth aspect, the present invention provides a catalyst system forolefin polymerization, comprising:

-   -   (1) the above-described solid catalyst component;    -   (2) an alkyl aluminum compound; and    -   (3) optionally, an external electron donor.

In some preferred embodiments of the present invention, the molar ratioof aluminum in the aluminum alkyl compound to titanium in the solidcatalyst component is (5-5000):1, preferably (20-800):1.

In some preferred embodiments of the present invention, the molar ratioof the alkylaluminum compound in terms of aluminum to the externalelectron donor compound is (0.1-500):1, preferably (1-100):1, and morepreferably (3-100):1.

According to some preferred embodiments of the present invention, thealkylaluminum compound is a compound represented by the general formulaAlR_(n)X_(3-n), wherein R is hydrogen, a hydrocarbon group with 1-20carbon atoms, especially alkyl, aralkyl, aryl group, etc.; X is ahalogen, and n is an integer of 1-3. Specifically, it can be at leastone of trimethylaluminum, triethylaluminum, triisobutylaluminum,trioctylaluminum, diethylaluminum hydride, diisobutylaluminum hydride,diethylaluminum chloride, diisobutylaluminum chloride,sesquiethylaluminum chloride and ethylaluminum dichloride, preferablytriethylaluminum and/or triisobutylaluminum.

According to the present invention, the external electron donor compoundis preferably an organosilicon compound. In some embodiments, theorganosilicon compound is represented by a general formula ofR_(n)Si(OR_(y))_(4-n), wherein n is an integer of from 0 to 3, R is oneor more of alkyl, cycloalkyl, aryl, halogenated alkyl, halogen andhydrogen, and Ry is one or more of alkyl, cycloalkyl, aryl andhalogenated alkyl; preferably, the organosilicon compound is at leastone of trimethylmethoxysilane, trimethylethoxysilane,trimethylphenoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane,methyltert-butyldimethoxysilane, diphenyldimethoxysilane,diphenyldiethoxysilane, dicyclohexyldimethoxysilane,phenyltrimethoxysilane, phenyltriethoxysilane, vinyltrimethoxysilane,methylcyclohexyldimethoxysilane, dicyclopentyldimethoxysilane,2-ethylpiperidinyl-2-tert-butyldimethoxysilane,(1,1,1-trifluoro-2-propyl)-2-ethylpiperidinyldimethoxysilane and(1,1,1-trifluoro-2-propyl)-methyldimethoxysilane, preferablymethylcyclohexyldimethoxysilane.

In a sixth aspect, the present invention provides use of theabove-described solid catalyst component or the above-described catalystsystem in an olefin polymerization reaction.

According to the present invention, the olefin polymerization catalystof the present invention can be used for the homopolymerization of anolefin or copolymerization of multiple olefins. At least one of theolefins is represented by the formula CH₂═CHR, wherein R is hydrogen ora C₁-C₆ linear or branched alkyl. Specific examples of the olefinrepresented by the formula CH₂═CHR may include ethylene, propylene,1-n-butene, 1-n-pentene, 1-n-hexene, 1-n-octene, and 4-methyl-1-pentene.Preferably, the olefin represented by the formula CH₂═CHR is one or moreof ethylene, propylene, 1-n-butene, 1-n-hexene and 4-methyl-1-pentene.More preferably, the olefin represented by the formula CH₂═CHR ispropylene, or a combination of propylene and other olefin(s).

In some preferred embodiments, the present invention provides use of theabove-described solid catalyst component or the above-described catalystsystem in the polymerization of propylene.

In a seventh aspect, the present invention provides a method for olefinpolymerization, comprising polymerizing an olefin in the presence of theabove-described solid catalyst component or the above-described catalystsystem.

According to the present invention, the olefin polymerization is carriedout according to known processes, in liquid phase of a liquid phasemonomer or a solution of a monomer in an inert solvent, or in gas phase,or by a combined polymerization process in gas phase and liquid phase.

In some preferred embodiments of the present invention, the conditionsfor the polymerization reaction include a temperature of from 0 to 150°C., preferably from 60 to 100° C. and a pressure of from 0.1 to 10.0MPa.

The beneficial effects of the present invention include at least thefollowings: the solid catalyst component has unique multimodal poredistribution characteristics, and the polymer prepared by using thecatalyst of the present invention in propylene polymerization has awider molecular weight distribution.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows the pore size distribution diagram of the magnesium-basedsolid prepared in Example 1, measured by nitrogen adsorption method andcalculated by NLDFT algorithm.

FIG. 2 shows the pore size distribution diagram of the magnesium-basedsolid prepared in Example 2, measured by nitrogen adsorption method andcalculated by NLDFT algorithm.

FIG. 3 shows the pore size distribution diagram of the magnesium-basedsolid prepared in Example 3, measured by nitrogen adsorption method andcalculated by NLDFT algorithm.

FIG. 4 shows the pore size distribution diagram of the magnesium-basedsolid prepared in Comparative Example 1, measured by nitrogen adsorptionmethod and calculated by NLDFT algorithm.

FIG. 5 shows the pore size distribution diagram of the catalystcomponent prepared in Example 7, measured by nitrogen adsorption methodand calculated by NLDFT algorithm.

FIG. 6 shows the pore size distribution diagram of the catalystcomponent prepared in Comparative Example 5, measured by nitrogenadsorption method and calculated by NLDFT algorithm.

FIG. 7 shows a microscope image of the magnesium-based solid prepared inExample 1.

EXAMPLES

The present invention will be illustrated in detail below by way ofexamples, but the protection scope of the present invention is notlimited to the following description.

If the specific conditions are not indicated in the examples, it iscarried out according to the conventional conditions or the conditionssuggested by the manufacturer. The reagents or instruments used withoutthe manufacturer's indication are conventional products that can beobtained through commercial channels.

In the following examples, the test methods involved are as follows:

-   -   1. Determination of titanium content in catalyst: colorimetric        determined by using UV-Vis spectrophotometer model 722.    -   2. Determination of magnesium content in catalyst: measured by        complexometric titration between magnesium ion and EDTA.    -   3. Particle size distribution of magnesium-containing carrier or        catalyst: measured by laser diffraction method, using Malvern        2000 particle size analyzer and n-hexane as a dispersant.    -   4. Determination of the content of the internal electron donor        compound in catalyst: after the catalyst dry powder is        decomposed by a dilute acid (such as dilute sulfuric acid,        etc.), the internal electron donor compound is extracted with an        extractant (such as hexane, etc.) and then determined by        chromatography, with an ether-type electron donor being        determined by using Agilent 6890N gas chromatograph, and an        ester-type electron donor being determined by using Waters 600E        high performance liquid chromatography.    -   5. Specific surface area and pore size distribution of        magnesium-containing carrier or catalyst: determined by nitrogen        adsorption method with ASAP 2460 specific surface area and        porosity analyzer from Micromeritics, USA.    -   6. Determination of polymer bulk density (BD): according to ASTM        D1895-96 standard.    -   7. Isotacticity index (II) of propylene polymer: determined by        heptane extraction method carried out as follows: 2 grams of dry        polymer sample were extracted with boiling heptane in an        extractor for 6 hours, then the residual substance was dried to        constant weight, and the ratio of the weight of the residual        polymer (g) to 2 (g) was regarded as isotacticity.    -   8. Molecular weight distribution MWD (MWD=Mw/Mn) of polymer:        determined by using PL-GPC220 with trichlorobenzene as solvent        at 150° C. (standards: polystyrene, flow rate: 1.0 ml/min,        columns: 3×Plgel 101.tm M1xED-B 300×7.5 nm).    -   9. Melt flow index (MI) of polymer: determined by using MI-4        melt flow index instrument from GOTTFERT company, German,        according to the GB/T 3682.1-2018 standard.

The examples given below are intended to illustrate the presentinvention, but not to limit the present invention.

Example 1

Example 1 is used to illustrate the preparation of a magnesium-basedsolid.

To a reactor, in which air had been repeatedly replaced with high-puritynitrogen, 10.86 g of anhydrous magnesium chloride, 249 mL of toluene,10.75 g of epichlorohydrin, and 70.7 g of tributyl phosphate weresuccessively added, and the contents were maintained at 60° C. under thestirring of 300 rpm for 2 hours. Then, 2.56 g of phthalic anhydride wasadded, and the contents were maintained at 60° C. for an additionalhour. The solution was cooled to 14° C. In advance, 2.1 g of surfactant(an alcoholysate of maleic anhydride-methacrylate copolymer, which iscommercially available from Guangzhou Ruishengyan Chemical TechnologyCo., Ltd. under the tradename T632) and 220 ml of food-grade No. 100white oil (having a kinematic viscosity at 40° C. of 100 mm²/s) weremixed uniformly to form mixture A. 151 ml of titanium tetrachloride andthe mixture A were simultaneously added dropwise thereto over 40 min.After the dropwise addition was completed, the contents were stirred at400 rpm for 1 hour. The temperature was then gradually increased to 80°C. over 3 hours, and the mother liquor was then filtered off. Theresidual solids were washed twice with hot toluene, then twice withhexane, and dried to obtain a titanium-containing, magnesium-basedsolid. The obtained solid had an average particle diameter D50 of 34.2μm, a SPAN value (i.e., (D90−D10)/D50) of 0.60, a titanium content of2.0% by weight, and a Mg content of 20.3% by weight. A micrograph of thesolid is shown in FIG. 7 .

The pore size distribution diagram of the solid, measured by nitrogenadsorption method and calculated by the NLDFT algorithm, is shown inFIG. 1 . It can be seen from FIG. 1 that the pore size distribution isshown as a multimodal pore size distribution, including at least onepeak in a pore size range below 10 nm and at least another peak in apore size range of not less than 10 nm.

The pore size data of the solid measured by nitrogen adsorption methodare given in Table 1.

Example 2

Example 2 is used to illustrate the preparation of a magnesium-basedsolid.

To a reactor, in which air had been repeatedly replaced with high-puritynitrogen, 10.86 g of anhydrous magnesium chloride, 194 mL of toluene,10.75 g of epichlorohydrin, and 75.12 g of tributyl phosphate weresuccessively added, and the contents were maintained at 60° C. withstirring for 2 hours. Then, 3.2 g of phthalic anhydride was added, andthe contents were maintained at 60° C. for an additional hour. Thesolution was cooled to 24° C., and 2.5 g of surfactant (an alcoholysateof maleic anhydride-methacrylate copolymer, which is commerciallyavailable from Guangzhou Ruishengyan Chemical Technology Co., Ltd. underthe tradename T632) diluted in 40 ml of toluene was then added thereto.The contents were continuously stirred for 1 hour, and 136 ml oftitanium tetrachloride and 240 ml of food-grade No. 100 white oil(having a kinematic viscosity at 40° C. of 100 mm²/s) were thensimultaneously added dropwise thereto over 40 min. After the dropwiseaddition was completed, the contents were stirred at 400 rpm for 1 hour.The temperature was then gradually increased to 80° C., and the motherliquor was then filtered off. The residual solids were washed twice withhot toluene, then twice with hexane, and dried to obtain atitanium-containing, magnesium-based solid. The obtained solid had anaverage particle diameter D50 of 62.1 μm, a SPAN value of 0.63, atitanium content of 2.3% by weight, and a Mg content of 21.1% by weight.

The pore size distribution diagram of the solid, measured by nitrogenadsorption method and calculated by the NLDFT algorithm, is shown inFIG. 2 . It can be seen from FIG. 2 that the pore size distribution isshown as a multimodal pore size distribution, including at least onepeak in a pore size range below 10 nm and at least another peak in apore size range of not less than 10 nm.

The pore size data of the solid measured by nitrogen adsorption methodare given in Table 1.

Example 3

A magnesium-based solid was prepared by the method described in Example1, except that the amount of the epichlorohydrin used was changed to14.2 g, the amount of the tributyl phosphate used was changed to 53.2 g,the amount of the toluene used was changed to 197 ml, and the amount ofthe titanium tetrachloride used was changed to 133 ml, and that afterthe addition of the phthalic anhydride and the maintaining at 60° C. foran additional hour, the solution was cooled to 8° C. The resulting solidhad a titanium content of 2.1% by weight and a Mg content of 21.2% byweight.

The pore size distribution diagram of the solid, measured by nitrogenadsorption method and calculated by the NLDFT algorithm, is shown inFIG. 3 . It can be seen from FIG. 3 that the pore size distribution isshown as a multimodal pore size distribution, including at least onepeak in a pore size range below 10 nm and at least another peak in apore size range of not less than 10 nm.

The pore size data of the solid measured by nitrogen adsorption methodare given in Table 1.

Example 4

A magnesium-based solid was prepared by the method described in Example1, except that the amount of the epichlorohydrin used was changed to 7.2g and the amount of the tributyl phosphate used was changed to 65.1 g,that the addition of the tributyl phosphate was followed by the additionof 2.2 g of ethanol, that the amount of the white oil used was changedto 184 ml and the amount of the titanium tetrachloride used was changedto 203 ml, and that after the addition of the phthalic anhydride and themaintaining at 60° C. for an additional hour, the solution was cooled to0° C. The resulting solid had a titanium content of 3.6% by weight and aMg content of 20.2% by weight.

The pore size data of the solid measured by nitrogen adsorption methodare given in Table 1, and the pore size distribution is a multimodalpore size distribution.

Example 5

A titanium-containing, magnesium-based solid was prepared by the methoddescribed in Example 1, except that the amount of the epichlorohydrinused was 10.75 g, the amount of the tributyl phosphate used was changedto 33.2 g, the amount of the toluene used was changed to 72 ml, theamount of the white oil used was changed to 120 ml, and the amount ofthe titanium tetrachloride used was changed to 112 ml, and that afterthe addition of the phthalic anhydride and the maintaining at 60° C. foran additional hour, the solution was cooled to 0° C. The resulting solidhad a titanium content of 2.6% by weight and a Mg content of 21.4% byweight.

The pore size data of the solid measured by nitrogen adsorption methodare given in Table 1, and the pore size distribution is a unimodal poresize distribution.

Comparative Example 1

A solid was prepared by the preparation method described in Example 1 inpatent CN107207657A, except that the surfactant VISCOPLEX was changed tothe surfactant used in Example 1 of the present invention. The obtainedsolid had an average particle diameter D50 of 27.1 a SPAN value of 1.24,a titanium content of 2.1% by weight, and a Mg content of 20.2% byweight.

The pore size data of the solid measured by nitrogen adsorption methodare given in Table 1, and the pore size distribution diagram is shown inFIG. 4 , which is a unimodal pore size distribution. FIG. 4 is a poresize distribution diagram using the NLDFT algorithm.

Comparative Example 2

A solid was prepared by the preparation method described in Example 1 inpatent CN1097597C, except that the electron donor diisobutyl phthalatewas not added and the subsequent steps were conducted as follows: afterthe precipitation of the solids, the mother liquor was filtered off, andthe solids were washed with hot toluene twice, then with hexane twice,and dried to obtain a titanium-containing, magnesium-based solid. Theobtained solid had an average particle diameter D50 of 24.1 μm, a SPANvalue of 1.14, a titanium content of 2.3% by weight, and a Mg content of21.1% by weight.

The pore size data of the solid measured by nitrogen adsorption methodare given in Table 1, and the pore size distribution is a unimodal poresize distribution.

TABLE 1 NLDFT algorithm Ratio of the The most The most pore volumeprobable probable with a pore pore size of pore size of ProportionProportion size <10 nm Catalyst the peak in the peak in of the pore ofthe pore to the pore Specific pore size the pore size the pore sizevolume with volume with volume with surface Pore distribution range ofless range of at a pore a pore a pore area volume Item profile than 10nm, nm least 10 nm, nm size <5 nm size ≥30 nm size ≥10 nm (m²/g) (cm³/g)Ex. 1 multimodal 3.2 86.2 0.652 0.144 4.81 205.59 0.218 Ex. 2 multimodal2.9 68.5 0.174 0.536 0.37 165.13 0.413 Ex. 3 multimodal 1.6 34.3 0.5550.291 1.58 227.79 0.274 Ex. 4 multimodal 4.6 73.9 0.738 0.056 8.02243.39 0.179 Ex. 5 unimodal 2.7 no peak 0.655 0.028 20.62 229.36 0.18Comp. Ex. 1 unimodal 4.3 no peak 0.663 0.02 35.71 184.86 0.182 Comp. Ex.2 unimodal 5 no peak 0.529 0.002 38.42 144.6 0.172 Notation: Under theNLDFT algorithm, the proportion of the pore volume with a pore size <5nm refers to the ratio of the pore volume with a pore size <5 nmobtained by the NLDFT algorithm to the total pore volume calculatedunder this algorithm, and the other representations have analogicalmeanings. The pore volumes given in Table 1 are the BJH algorithm porevolume.

Example 6

A. Preparation of Solid Catalyst Component

To a reactor, in which air had been repeatedly replaced with high-puritynitrogen, 10.86 g of anhydrous magnesium chloride, 249 mL of toluene,10.75 g of epichlorohydrin, and 70.7 g of tributyl phosphate weresuccessively added, and the contents were maintained at 60° C. under thestirring of 300 rpm for 2 hours. Then, 2.5 g of phthalic anhydride wasadded, and the contents were maintained at 60° C. for an additionalhour. The solution was cooled to 15° C. In advance, 2.1 g of surfactant(an alcoholysate of maleic anhydride-methacrylate copolymer, which iscommercially available from Guangzhou Ruishengyan Chemical TechnologyCo., Ltd. under the tradename T632) and 220 ml of food-grade No. 100white oil (having a kinematic viscosity at 40° C. of 100 mm²/s) weremixed uniformly to form mixture 1. 151 ml of titanium tetrachloride andthe mixture 1 were simultaneously added dropwise thereto over 40 min.After the dropwise addition was completed, the contents were stirred at400 rpm for 1 hour. The temperature was then gradually increased to 80°C. over 3 hours, 3 mL of di-n-butyl phthalate as an electron donor wasthen added thereto, and the temperature was raised to 85° C. and thenkept constant for 1 hour. After filtration, the residual solids werewashed twice with hot toluene. Next, 80 mL of titanium tetrachloride and120 mL of toluene were added thereto, and the contents were maintainedat a constant temperature of 110° C. for 0.5 hours and then filtered,and the operation was repeated once. Then, the obtained solids werewashed 5 times with hexane and then dried under vacuum to obtain a solidcatalyst component for olefin polymerization. The data of the catalystcomponent are given in Table 3.

The pore size data of the solids measured by nitrogen adsorption methodare given in Table 2. The pore size distribution of the catalyst is amultimodal pore size distribution.

B. Propylene Polymerization

At room temperature, to a 5-liter autoclave, in which the atmosphere hadbeen fully replaced by nitrogen, were charged with 5 mL of a solution oftriethylaluminum in hexane (having a triethylaluminum concentration of0.5 mmol/mL), 1 mL of a solution of cyclohexylmethyldimethoxysilane(CHMMS) in hexane (having a CHMMS concentration of 0.1 mmol/mL), 10 mLof anhydrous hexane and 10 mg of the catalyst component from Example 6.One liter of hydrogen in standard state and 1.15 kg of liquid propylenewere introduced thereinto. The temperature was raised to 70° C., and thepolymerization was carried out at 70° C. for 1 hour. After the reactionwas completed, the autoclave was cooled and the stirring was stopped,and then the reaction product was discharged to obtain an olefinpolymer. The polymerization results of the catalyst and the polymer dataare given in Table 3.

Example 7

A. Preparation of Solid Catalyst Component

To a reactor, in which air had been repeatedly replaced with high-puritynitrogen, 10.86 g of anhydrous magnesium chloride, 272 mL of toluene,9.76 g of epichlorohydrin, and 78 g of tributyl phosphate weresuccessively added, and the contents were maintained at 60° C. under thestirring of 300 rpm for 2 hours. Then, 3 g of phthalic anhydride wasadded, and the contents were maintained at 60° C. for an additionalhour. The solution was cooled to 10° C. In advance, 3.2 g of surfactant(an alcoholysate of maleic anhydride-methacrylate copolymer, which iscommercially available from Guangzhou Ruishengyan Chemical TechnologyCo., Ltd. under the tradename T632) and 240 ml of food-grade No. 100white oil (having a kinematic viscosity at 40° C. of 100 mm²/s) weremixed uniformly to form mixture 1. 135 ml of titanium tetrachloride andthe mixture 1 were simultaneously added dropwise thereto over 40 min.After the dropwise addition was completed, the contents were stirred at400 rpm for 2 hours. The temperature was then gradually increased to 85°C. over 3 hours, with 3 mL of 2,4-pentanediol dibenzoate as an electrondonor being added during the temperature increasing, and the temperaturewas then kept constant at 85° C. for 1 hour. After filtration, theresidual solids were washed twice with hot toluene. Next, 80 mL oftitanium tetrachloride and 120 mL of toluene were added thereto, and thecontents were maintained at a constant temperature of 110° C. for 0.5hours and then filtered, and the operation was repeated once. Then, theobtained solids were washed 5 times with hexane and then dried undervacuum to obtain a solid catalyst component for olefin polymerization.The data of the catalyst component are given in Table 3.

The pore size distribution diagram of the solid, measured by nitrogenadsorption method and calculated by the NLDFT algorithm, is shown inFIG. 5 . It can be seen from FIG. 5 that the pore size distribution isshown as a multimodal pore size distribution, including at least onepeak in a pore size range below 10 nm and at least another peak in apore size range of not less than 10 nm. The pore size data of the solidsmeasured by nitrogen adsorption method are given in Table 2.

B. Propylene Polymerization

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Example 8

A. Preparation of Solid Catalyst Component

To a reactor, in which air had been repeatedly replaced with high-puritynitrogen, 10.86 g of anhydrous magnesium chloride, 211 mL of toluene,11.5 g of epichlorohydrin, and 68 g of tributyl phosphate weresuccessively added, and the contents were maintained at 60° C. withstirring for 2 hours. Then, 2.5 g of phthalic anhydride was added, andthe contents were maintained at 60° C. for an additional hour. Thesolution was cooled to 0° C., 3 g of 9,9-dimethoxymethylfluorene wasadded thereto, and the contents were continuously stirred for 60 min. Inadvance, 2.5 g of surfactant (an alcoholysate of maleicanhydride-methacrylate copolymer, which is commercially available fromGuangzhou Ruishengyan Chemical Technology Co., Ltd. under the tradenameT632) and 260 ml of food-grade No. 100 white oil (having a kinematicviscosity at 40° C. of 100 mm²/s) were mixed uniformly to formmixture 1. 165 ml of titanium tetrachloride and the mixture 1 weresimultaneously added dropwise thereto over 40 min. After the dropwiseaddition was completed, the contents were stirred at 400 rpm for 1 hour.The temperature was then gradually increased to 85° C. over 4 hours andthen kept constant for 1 hour. After filtration, the residual solidswere washed twice with hot toluene. Next, 80 mL of titaniumtetrachloride and 120 mL of toluene were added thereto, and the contentswere maintained at a constant temperature of 110° C. for 0.5 hours andthen filtered, and the operation was repeated once. Then, the obtainedsolids were washed 5 times with hexane and then dried under vacuum toobtain a solid catalyst component for olefin polymerization. The data ofthe catalyst component are given in Table 3.

The pore size data of the solids measured by nitrogen adsorption methodare given in Table 2. The pore size distribution of the catalyst is amultimodal pore size distribution.

B. Propylene Polymerization

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Example 9

A. Preparation of Solid Catalyst Component

The procedure was substantially the same as Example 6, except that theamount of the epichlorohydrin was changed to 14.2 g, the amount of thetributyl phosphate was changed to 53.2 g, the amount of the toluene waschanged to 197 ml, and the amount of the titanium tetrachloride waschanged to 133 ml, and that after the addition of the phthalic anhydrideand the maintaining at 60° C. for an additional hour, the solution wascooled to 8° C. Catalyst component data are given in Table 3.

The pore size data of the catalyst measured by nitrogen adsorptionmethod are given in Table 2. The pore size distribution of the catalystis a multimodal pore size distribution.

B. Propylene Polymerization

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Example 10

A. Preparation of Solid Catalyst Component

The procedure was substantially the same as Example 6, except that theamount of the epichlorohydrin used was changed to 7.2 g and the amountof the tributyl phosphate used was changed to 65.1 g, that the additionof the tributyl phosphate was followed by the addition of 2.2 g ofethanol, that the amount of the white oil used was changed to 184 ml andthe amount of the titanium tetrachloride used was changed to 203 ml, andthat after the addition of the phthalic anhydride and the maintaining at60° C. for an additional hour, the solution was cooled to 0° C. Catalystcomponent data are given in Table 3.

The pore size data of the solids measured by nitrogen adsorption methodare given in Table 2. The pore size distribution of the catalyst is amultimodal pore size distribution.

B. Propylene Polymerization

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Example 11

A. Preparation of Solid Catalyst Component

To a reactor, in which air had been repeatedly replaced with high-puritynitrogen, were successively charged with 10.86 g of anhydrous magnesiumchloride, 104 g of toluene, 10.5 g of epichlorohydrin, 70.0 g oftributyl phosphate, and 1.5 mL of ethylene glycol dibutyl ether, and thecontents were maintained at 60° C. with stirring of 300 rpm for 2 hours.Then, 3.4 g of phthalic anhydride was added, and the contents werecontinuously stirred at 60° C. for an additional hour. The solution wascooled to 14° C., and the stirring speed was increased to 400 rpm. Inadvance, 128.5 g of food-grade No. 100 white oil (having a kinematicviscosity at 40° C. of 100 mm²/s) and 5.7 g of surfactant (T602,commercially available from Guangzhou Ruishengyan Chemical TechnologyCo., Ltd.) were mixed to form mixture 1. 181.7 ml of titaniumtetrachloride and the mixture 1 were simultaneously added dropwisethereto over 60 min. After the dropwise addition was completed, thecontents were maintained for 1 hour to obtain mixture 2. The temperaturewas gradually increased to 80° C., 2.0 mL of2-isopropyl-2-isopentyl-1,3-dimethoxypropane was added, and thetemperature was raised to 85° C. and maintained for 1 hour. Afterfiltering off the supernatant, the residual solids were washed threetimes with 200 mL of toluene. Next, the solids were treated with 120 mLof toluene and 80 mL of titanium tetrachloride at 90° C. for 1 hour, andthen the liquid was filtered off. Then, the solids were treated with 120mL of toluene and 80 mL of titanium tetrachloride at 110° C. for 1 hour,and then the liquid was filtered off. Next, the solids were washed 4times with 200 mL of hexane, to afford a solid catalyst component forolefin polymerization. The catalyst physical property data are given inTable 3, and the catalyst pore size data are given in Table 2.

B. Propylene Polymerization

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Example 12

A. Preparation of Solid Catalyst Component

To a reactor, in which air had been repeatedly replaced with high-puritynitrogen, were successively charged with 10.86 g of anhydrous magnesiumchloride, 104 g of toluene, 7.2 g of epichlorohydrin, 75.2 g of tributylphosphate, and 1.5 mL of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane,and the contents were maintained at 60° C. with stirring of 300 rpm for2 hours. Then, 4.59 g of phthalic anhydride was added, and the contentswere maintained at 60° C. for an additional hour. The solution wascooled to 14° C., and the stirring speed was increased to 400 rpm. Inadvance, 128.5 g of food-grade No. 100 white oil (having a kinematicviscosity at 40° C. of 100 mm²/s) and 5.7 g of surfactant (T602,commercially available from Guangzhou Ruishengyan Chemical TechnologyCo., Ltd.) were mixed to form mixture 1. 81.7 ml of titaniumtetrachloride and the mixture 1 were simultaneously added dropwisethereto over 60 min. After the dropwise addition was completed, thecontents were maintained for 1 hour. The temperature was graduallyincreased to 80° C. and maintained for 1 hour. After filtering off thesupernatant, the residual solids were washed two times with 200 mL oftoluene. Next, 160 mL of toluene, 40 mL of titanium tetrachloride and2.6 mL of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added, andthe temperature was raised to 85° C. and maintained for 2 hours. Afterfiltering off the liquid, the solids were treated with 120 mL of tolueneand 80 mL of titanium tetrachloride at 90° C. for 1 hour, and then theliquid was filtered off. Then, the solids were treated with 120 mL oftoluene and 80 mL of titanium tetrachloride at 110° C. for 1 hour, andthen the liquid was filtered off. Next, the solids were washed 5 timeswith 200 mL of hexane, to afford a solid catalyst component for olefinpolymerization. The catalyst physical property data are given in Table3, and the catalyst pore size data are given in Table 2.

B. Propylene Polymerization

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Example 13

A. Preparation of Solid Catalyst Component

To a reactor, in which air had been repeatedly replaced with high-puritynitrogen, were successively charged with 10.86 g of anhydrous magnesiumchloride, 104 g of toluene, 12.43 g of epichlorohydrin, and 75.2 g oftributyl phosphate, and the contents were maintained at 60° C. withstirring of 300 rpm for 2 hours. Then, 4.59 g of phthalic anhydride wasadded, and the contents were maintained at 60° C. for an additionalhour. The solution was cooled to 14° C., and the stirring speed wasincreased to 400 rpm. In advance, 128.5 g of food-grade No. 100 whiteoil (having a kinematic viscosity at 40° C. of 100 mm²/s) and 5.7 g ofsurfactant (T602, commercially available from Guangzhou RuishengyanChemical Technology Co., Ltd.) were mixed to form mixture 1. 81.7 ml oftitanium tetrachloride and the mixture 1 were simultaneously addeddropwise thereto over 60 min. After the dropwise addition was completed,the contents were maintained for 1 hour. The temperature was graduallyincreased to 80° C. and maintained for 1 hour. After filtering off thesupernatant, the residual solids were washed two times with 200 mL oftoluene. Next, 160 mL of toluene, 40 mL of titanium tetrachloride and3.6 mL of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added, andthe temperature was raised to 85° C. and maintained for 2 hours. Afterfiltering off the liquid, the solids were treated with 120 mL of tolueneand 80 mL of titanium tetrachloride at 90° C. for 1 hour, and then theliquid was filtered off. Then, the solids were treated with 120 mL oftoluene and 80 mL of titanium tetrachloride at 110° C. for 1 hour, andthen the liquid was filtered off. Next, the solids were washed 5 timeswith 200 mL of hexane, to afford a solid catalyst component for olefinpolymerization. The catalyst physical property data are given in Table3, and the catalyst pore size data are given in Table 2.

B. Propylene Polymerization

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Comparative Example 3

A. Preparation of Solid Catalyst Component

The procedure was substantially the same as Example 6, except that theamount of the epichlorohydrin used was 10.75 g, the amount of thetributyl phosphate used was changed to 33.2 g, the amount of the tolueneused was changed to 72 ml, the amount of the white oil used was changedto 120 ml, and the amount of the titanium tetrachloride used was changedto 112 ml, and that after the addition of the phthalic anhydride and themaintaining at 60° C. for an additional hour, the solution was cooled to0° C. Catalyst component data are given in Table 3.

The pore size data of the catalyst measured by nitrogen adsorptionmethod are given in Table 2. The pore size distribution of the catalystis a unimodal pore size distribution.

B. Propylene Polymerization

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Comparative Example 4

A. Preparation of Solid Catalyst Component

The procedure was substantially the same as Example 6, except that theamount of the tributyl phosphate used was changed to 38.8 g. Catalystcomponent data are given in Table 3.

The pore size data of the catalyst measured by nitrogen adsorptionmethod are given in Table 2. The pore size distribution of the catalystis a unimodal pore size distribution.

B. Propylene Polymerization

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Comparative Example 5

A solid was prepared by the preparation method described in Example 1 inpatent CN107207657A, except that the surfactant VISCOPLEX was changed tothe surfactant used in Example 1. The solid was then maintained,together with 260 ml of a 20% titanium tetrachloride solution in tolueneand 3 ml of di-n-butyl phthalate electron donor, at 85° C. for 1 hour.After filtering, the solids were washed twice with toluene. Then, 100 mlof titanium tetrachloride and 150 ml of toluene were added thereto, thetemperature was maintained constant at 110° C. for 0.5 hours, and thenthe liquid was filtered off. This operation was repeated once. Then, theobtained solids were washed 5 times with hexane and then vacuum-dried toobtain a solid catalyst component for olefin polymerization. Catalystcomponent data are given in Table 3.

The pore size distribution diagram of the solids, measured by nitrogenadsorption method and calculated by the NLDFT algorithm, is shown inFIG. 6 .

The pore size data of the catalyst measured by nitrogen adsorptionmethod are given in Table 2. The pore size distribution of the catalystis a unimodal pore size distribution.

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Comparative Example 6

A solid was prepared by the preparation method of Example 1 in patentCN1097597C, except that diisobutyl phthalate was changed to 1.5 g of9,9-dimethoxymethylfluorene. Catalyst component data are given in Table3.

The pore size data of the catalyst measured by nitrogen adsorptionmethod are given in Table 2. The pore size distribution of the catalystis a unimodal pore size distribution.

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Comparative Example 7

A solid was prepared by the preparation method of Example 1 in patentCN1097597C, except that diisobutyl phthalate was changed to 1.5 ml of2,4-pentanediol dibenzoate. Catalyst component data are given in Table3.

The pore size data of the catalyst measured by nitrogen adsorptionmethod are given in Table 2. The pore size distribution of the catalystis a unimodal pore size distribution.

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

Comparative Example 8

A solid was prepared by the preparation method of Example 1 in patentCN1097597C, except that diisobutyl phthalate was changed to 1.5 ml of2-isopropyl-2-isopentyl-1,3-dimethoxypropane. Catalyst component dataare given in Table 3.

The pore size data of the catalyst measured by nitrogen adsorptionmethod are given in Table 2. The pore size distribution of the catalystis a unimodal pore size distribution.

Propylene polymerization method was the same as described for Example 6,and the polymerization data of the catalyst and the polymer data aregiven in Table 3.

TABLE 2 NLDFT algorithm The most The most probable probable pore size ofpore size of Proportion Proportion Catalyst the peak in the peak in ofthe pore of the pore Specific pore size the pore size the pore sizevolume with volume with surface Pore distribution range of less range ofat a pore a pore area volume Item profile than 10 nm, nm least 10 nm, nmsize <5 nm size ≥30 nm (m²/g) (cm³/g) Example 6 multimodal 3.4 82.00.648 0.166 264.62 0.288 Example 7 multimodal 2.7 68.5 0.503 0.312156.71 0.200 Example 8 multimodal 2.3 68.5 0.245 0.501 316.91 0.447Example 9 multimodal 1.6 34.2 0.505 0.331 332.56 0.395 Example 10multimodal 4.0 71.1 0.701 0.076 373.39 0.301 Example 11 multimodal 2.968.5 0.553 0.285 299.09 0.333 Example 12 multimodal 4.6 31.7 0.672 0.088347.21 0.271 Example 13 multimodal 2.7 42.5 0.186 0.571 208.28 0.437Comp. Ex. 3 unimodal 2.7 no peak 0.792 0.022 314.90 0.204 Comp. Ex. 4unimodal 2.9 no peak 0.763 0.033 316.76 0.224 Comp. Ex. 5 unimodal 4.0no peak 0.752 0.007 399.93 0.323 Comp. Ex. 6 unimodal 3.8 no peak 0.5310.002 202.32 0.197 Comp. Ex. 7 unimodal 4.0 no peak 0.509 0.002 218.510.212 Comp. Ex. 8 unimodal 3.8 no peak 0.551 0.002 233.02 0.222Notation: Under the NLDFT algorithm, the proportion of the pore volumewith a pore size <5 nm refers to the ratio of the pore volume with apore size <5 nm obtained by the NLDFT algorithm to the total pore volumecalculated under this algorithm, and the other representations haveanalogical meanings. The pore volumes given in Table 2 are the BJHalgorithm pore volume.

TABLE 3 Internal electron Polymerization Ti Mg donor activity BD II MIItem wt % wt % wt % KgPP/gCat g/cm³ wt % (g/10 min) MWD Example 6 1.7818.3 8.4 38.4 0.43 98.3 4.3 6.1 Example 7 1.83 18.1 10.4 34.4 0.42 98.54.7 8.4 Example 8 1.83 18.1 9.4 54.7 0.44 98.5 3.7 5.2 Example 9 1.6318.2 9.1 32.3 0.40 98.1 4.5 6.2 Example 10 3.62 17.5 9.3 28.8 0.39 98.43.3 5.7 Example 11* 1.94 17.7 9.2 58.2 0.43 98.0 3.5 5.8 Example 12 2.2818.4 9.5 72.4 0.43 98.7 3.8 4.7 Example 13 1.78 18.7 9.5 56.1 0.42 98.53.8 4.9 Comp. Ex. 3 1.58 18.4 8.7 37.1 0.47 97.6 5.1 4.9 Comp. Ex. 41.82 18.3 8.7 32.5 0.45 97.8 3.6 5.3 Comp. Ex. 5 1.34 18.7 9.2 24.8 0.3997.7 4.6 4.8 Comp. Ex. 6 2.13 18.6 9.9 54.1 0.45 98.1 3.8 3.7 Comp. Ex.7 2.12 18.5 10.1 50.4 0.42 98.4 4.5 6.7 Comp. Ex. 8 2.10 18.3 9.4 42.10.45 97.5 3.6 3.2 *The content of internal electron donor for Example 11is the content of 2-isopropyl-2-isopenty1-1,3-dimethoxypropane.

It can be seen from the data in Tables 1-3 and FIGS. 1-6 that thetitanium-containing, magnesium-based solids and the magnesiumchloride-supported olefin polymerization catalyst components obtained bythe present invention have multimodal pore size distributioncharacteristics and higher specific surface areas, whereas the magnesiumchloride-supported olefin polymerization catalysts shown in thecomparative examples have unimodal pore size distributioncharacteristics. When the catalysts of the present invention are usedfor propylene polymerization, they have higher polymerization activitiesand higher stereo-orientation abilities, and the prepared polymers havewider molecular weight distribution.

It should be noted that the foregoing embodiments are only used toexplain the present invention, and do not constitute any limitation tothe present invention. The present invention has been described withreference to typical embodiments, but it should be understood that thewords used therein are descriptive and explanative, rather thanlimitative. The present invention may be modified within the scope ofthe claims of the present invention as specified, and may be modifiedwithout departing from the scope and spirit of the present invention.Although the invention described herein refers to the specific methods,materials and embodiments, it is not intended to be limited to thespecific examples disclosed therein, but rather, the invention extendsto all other methods and applications having the same function.

1. A magnesium-based solid with a multimodal pore distribution, whichcomprises a magnesium halide as a carrier and titanium element, wherein,as determined by a nitrogen adsorption method, the magnesium-based solidhas a specific surface area of not less than 50 m²/g and a pore sizedistribution in a range of from 1 nm to 300 nm, wherein there are atleast one peak within the pore size range of less than 10 nm and atleast one peak within the pore size range of not less than 10 nm;preferably, the peak within the pore size range of less than 10 nm has amost probable pore size of from 2 nm to 8 nm, and preferably from 2 nmto 6 nm, and the peak within the pore size range of not less than 10 nmhas a most probable pore size of from 15 nm to 200 nm, preferably from20 nm to 100 nm, and more preferably from 30 nm to 90 nm.
 2. Themagnesium-based solid as claimed in claim 1, characterized in that inthe magnesium-based solid, the ratio of the pore volume of pores with apore size of less than 10 nm to the pore volume of pores with a poresize of not less than 10 nm is (0.1-20):1, and preferably (0.25-15):1.3. The magnesium-based solid as claimed in claim 1, characterized inthat the pore volume of pores with a pore size of less than 5 nmaccounts for 10% to 90% of the total pore volume, and preferably 15% to70%; and the pore volume of pores with a pore size of not less than 30nm accounts for 5% to 70% of the total pore volume, and preferably 10%to 60%.
 4. A method for preparing the magnesium-based solid as claimedin claim 1, comprising: S1. contacting a magnesium halide with a Lewisbase in an organic solvent to form a magnesium-containing solution; S2.contacting the magnesium-containing solution with an inert dispersionmedium and a Lewis acid to form a mixture; S3. in the presence of anauxiliary precipitant and a surfactant, precipitating themagnesium-based solid from the mixture, wherein, in step S1, the Lewisbase includes an organic phosphorus compound, which is used in an amountof from 1.5 to 10 moles, preferably from 2 to 5 moles, per mole of themagnesium halide; more preferably, the Lewis base further includes anorganic epoxy compound; and in step S2, the Lewis acid includes atitanium compound.
 5. The method as claimed in claim 4, characterized inthat in step S1, the magnesium halide is represented by a generalformula (1):MgX¹ ₂  (1), wherein X¹ is a halogen, preferably chlorine, bromine oriodine, preferably the magnesium halide is magnesium dichloride; and/orthe organic phosphorus compound is one or more of the compoundsrepresented by formula (2) or formula (3):

wherein R₁, R₂, R₃, R₄, R₅, R₆ each independently have 1-20 carbon atomsand are selected from the group consisting of linear or branched alkylgroups, cycloalkyl groups, aromatic hydrocarbon groups, and aromatichydrocarbon groups having a substituent, preferably the organicphosphorus compound is one or more of trimethyl phosphate, triethylphosphate, tributyl phosphate, tripentyl phosphate, triphenyl phosphate,trimethyl phosphite, triethyl phosphite, tributyl phosphite andtribenzyl phosphite; and/or the organic solvent is one or more selectedfrom the group consisting of aromatic hydrocarbon compounds andhalogenated hydrocarbon compounds, preferably the organic solvent is oneor more of toluene, ethylbenzene, benzene, xylenes and chlorobenzene,and more preferably the organic solvent is used in an amount of from 1to 40 moles, and preferably from 2 to 30 moles, relative to one mole ofthe magnesium halide.
 6. The method as claimed in claim 4, characterizedin that, in step S2, the inert dispersion medium is one or more selectedfrom the group consisting of kerosenes, paraffin oils, white oils,vaseline oils, methyl silicone oils, aliphatic and cycloaliphatichydrocarbons, preferably the inert dispersion medium is one or more ofwhite oils, hexanes and decanes, and more preferably the inertdispersion medium is used in an amount of from 0.1 g to 300 g,preferably from 1 g to 150 g, relative to one gram of the magnesiumhalide; and/or the Lewis acid comprises a titanium-containing compoundrepresented by general formula (4):TiX² _(m)(OR¹)_(4-m)  (4) wherein X² is a halogen, preferably chlorine,bromine or iodine, le is a hydrocarbon group having 1-20 carbon atoms,and m is an integer of 1 to 4, preferably the titanium-containingcompound is one or more of titanium tetrachloride, titaniumtetrabromide, titanium tetraiodide, titanium tetrabutoxide, titaniumtetraethoxide, triethoxy titanium chloride, diethoxy titanium dichlorideand ethoxy titanium trichloride, and more preferably thetitanium-containing compound is used in an amount of from 0.5 to 25moles, preferably from 1 to 20 moles, relative to one mole of themagnesium halide.
 7. The method as claimed in claim 4, characterized inthat, in step S3, the auxiliary precipitant is one or more selected fromthe group consisting of organic acids, organic acid anhydrides, organicethers and organic ketones, preferably the auxiliary precipitant is oneor more selected from the group consisting of acetic anhydride, phthalicanhydride, succinic anhydride, maleic anhydride, pyromelliticdianhydride, acetic acid, propionic acid, butyric acid, acrylic acid,methacrylic acid, acetone, methyl ethyl ketone, benzophenone, dimethylether, diethyl ether, dipropyl ether, dibutyl ether and dipentyl ether,and more preferably the auxiliary precipitant is used in an amount offrom 0.01 to 1 mole, preferably from 0.04 to 0.4 moles, relative to onemole of the magnesium halide; and/or the surfactant is a polymericsurfactant, preferably the surfactant is one or more selected from thegroup consisting of alkyl (meth)acrylate polymers, alkyl (meth)acrylatecopolymers, alcoholysates of maleic anhydride polymers, andalcoholysates of maleic anhydride copolymers, and more preferably thesurfactant is used in an amount of from 0.01 g to 5 g, preferably from0.05 g to 1 g, relative to one gram of the magnesium halide.
 8. A solidcatalyst component for olefin polymerization with a multimodal poredistribution, which comprises the magnesium-based solid as claimed inclaim 1 and at least one internal electron donor.
 9. The solid catalystcomponent as claimed in claim 8, characterized in that, as measured bynitrogen adsorption method, the solid catalyst component has a pore sizedistribution exhibiting multiple peaks and a specific surface area ofnot less than 50 m²/g; wherein the pore size distribution exhibitingmultiple peaks of the solid is such that there are at least a first peakin the pore size range of 1 nm-10 nm and at least a second peak in thepore size range of 10 nm-200 nm.
 10. The solid catalyst component asclaimed in claim 8, characterized in that, the pore size distributionexhibiting multiple peaks of the solid is such that the peak in the poresize range of 1 nm-10 nm has a most probable pore size of from 2 nm to 8nm, and further preferably from 2 nm to 6 nm; and the peak in the poresize range of 10 nm-200 nm has a most probable pore size of from 15 nmto 200 nm, preferably from 20 nm to 100 nm, and more preferably from 30nm to 90 nm.
 11. The solid catalyst component as claimed in claim 8,characterized in that, the pore volume of pores with a pore size of lessthan 5 nm accounts for 10% to 90%, preferably 15% to 70% of the totalpore volume; and the pore volume of pores with a pore size of not lessthan 30 nm accounts for 5% to 70%, preferably 10% to 60% of the totalpore volume.
 12. The solid catalyst component as claimed in claim 8,wherein the internal electron donor is one or more selected from thegroup consisting of esters, ethers, ketones, amines, and silanes,preferably at least one of aliphatic mono- or poly-carboxylic acidesters, aromatic carboxylic acid esters, diol ester compounds anddiether compounds, and preferably includes at least one of dibasicaliphatic carboxylic acid esters, aromatic carboxylic acid esters, diolesters and diether compounds, and more preferably includes at least oneof phthalates, malonates, succinates, glutarates, diol esters, diethers,neovalerates and carbonates.
 13. A method for preparing the solidcatalyst component for olefin polymerization as claimed in claim 8,comprising adding at least one internal electron donor during thepreparation of the magnesium-based solid; or/and contacting at least oneinternal electron donor with the magnesium-based solid, to obtain thesolid catalyst component for olefin polymerization.
 14. A catalystsystem for olefin polymerization, comprising (1) the solid catalystcomponent as claimed in claim 8; (2) an alkyl aluminum compound; and (3)optionally, an external electron donor.
 15. A method for olefinpolymerization, comprising polymerizing an olefin monomer in thepresence of the solid catalyst component as claimed in claim
 8. 16. Amethod for olefin polymerization, comprising polymerizing an olefinmonomer in the presence of the catalyst system as claimed in claim 14.